Full cycle positioning means



Dec. 2, 1947.

E. GRIP ET AL FULL CYCLE POSITIONING MEANS 4 Sheets-Sheet 1 Filed May 5,, 1944 lNVEA/TORS,

,0 and STU/",6 Too/"ell Dec. 2, 1947.

E. GRIP ETAL FULL CYCLE POSITIONING MEANS 4 Sheets-Sheet 2 I Filed May '5, 1944 /N VENT'OR-S,

Er/K Gr/p and S/ur'e Toorel/ By M Afforney Dec. 2, 1947. E. GRIP ETAL FULL CYCLE POSITIONING MEANS w .MDIO

% v Um mw W66 4 Kr Tw E8 I M A fforney Dec. 2, 1947. E. GRIP ETAL 2,431,930

FULL CYCLE POSITIONING MEANS Filed May' 5, 1944 4 Sheets-Sheet 4 N VEN TOR S 4/2 Er/K Grip and 8 fun; Toore'l/ Affornqy.

Patented Dec. 2, 1947 FULL CYCLE POSITIONING MEANS Erik Grip and Sture Toorell, Atvidaberg, Sweden, assignors to Aktiebolaget Facit, Atvidaberg, Sweden, a corporation of Sweden Application May 5, 1944, Serial No. 534,287 In Sweden May 19, 1943 13 Claims.

This invention relates to calculating machines and more particularly to multiplying machines having an actuator to be operated in two directions, that is the direction and the direction. It may be applied, for instance, to pin wheel or Odhner machines.

The chief purpose of this invention is to simplify the devices for stopping the rotary actuator (such as a pin-wheel rotor) after completing the desired number of revolutions, and also to improve such stopping devices for rendering them more reliable.

Another purpose of this invention is to lower the costs for manufacturing the stopping devices for the actuator.

Another purpose of this invention is to render the machine more reliable and less sensitive to shocks and rough handling; in other words the risk of machine faults is essentially reduced. This is of course most important in rapidly operating calculating machines driven by electric motors.

When not otherwise expressly stated, the expressions right, left, upwards, down wards, forwards, backwards, front and back are used in this specification and in the claims as such directions appear to an operator sitting at the key-board of the machine to manipulate it.

One embodiment of an improved calculating machine in accordance with this invention is il-' lustrated in the annexed drawings.

Fig. lshows a section on the line 1'-I of Fig. 2 and i substantially an end view from the right side of the machine, with the right end plate removed.

Fig. 2 shows a front view of the upper part of the driving mechanism proper.

Fig. 3 shows a detail view of the stop disc mechanism, as viewed from above.

Fig. 4 shows a top view of the driving mechanism proper.

Fig. 5 shows an end view of certain details immediately to the left of the driving mechanism proper.

Fig. 6 is a cross-sectional view taken on the line VI-VI of Fig. 1.

Fig. 7 is a cross-sectional view taken on the line VII-VII of Fig. 1, showing a uiding plate.

Fig. 8 is a plan view of a part of the stop disc, and is taken on the line VIII-VIII of Fig. 3.

Fig. 9 is a cross-sectional view taken on the line IXIX of Fig. 8.

Fig. 10 shows a plan View of one of the buffer discs in the stop disc mechanism.

Fig. 11 shows an end view of the clearing mechanism and the parts cooperating therewith.

Fig. 12 shows a detail (a side view) of the setting arm for setting the machine to direct subtraction, together with the parts cooperating therewith.

The machine illustrated in the drawings is in its essential features constructed in accordance with U. S. Patents No. 2,108,596, No. 1,927,771, No. 2,243,075 and No. 2,398,286 issued April 9, 1946, though the invention by no means is limited thereto. See also U. S. patent applications Ser. No. 532,961, Ser. No. 534,453 and Ser. No. 543,288 corresponding to Swedish patent applications No. 7448/1942 and 7449/1942 and 3605/43, respectively.

The machine illustrated in the drawings is of the Odhner or pin wheel type and has an actuator or pin wheel rotor arranged in a carriage shifta'ble along the main shaft 58. For carrying out the calculating operations this shaft together with the actuator is rotated in either direction of rotation, that is or direction, that is, counterclockwise and clockwise, respectively, in Figs. 1 and 11, asindicated by arrows correspondingly marked.

A shaft I9 is driven by a motor and carries a toothed wheel I! driving a toothed wheel I241, which together with another toothed wheel 12b (Figs. 1 and 4) is secured to a shaft IS. The toothed wheel [2a drives directly a toothed wheel 14, while the toothed wheel lZb drives a toothed wheel I 5 through an intermediate toothed wheel IT. The two toothed wheels l4, 15 are freely journalled on the shaft 16 and consequently they always rotate in opposite directions as long as the motor runs. One or the other of these toothed wheels l4, [5 may be coupled to the shaft I6 by means of the coupling pawl it, which is rockable on a pin lea. This pin extends at right angles to the shaft [6, and is secured in the block I9 rigidly attached to the shaft l6 and passes through a slot in said block. Said slot is parallel with the shaft is and in it the pawl I8 is thus journalled. When said pawl is rocked in one direction or the other, its lateral projections will engage shoulders or off-sets on the sides of the toothed wheels 14 and I5, respectively. This couples the shaft I6 to the toothed wheel 14 or l5, respectively, that is, this shaft is rotated in one direction or the other, because the wheels is and I5 rotate in opposite directions. By means of geared transmissions the shaft 15 is in permanent driving connection with the main shaft 58 of the machine, which carries the actuator.

Thus, the actuator is rotated in the direction or the direction depending on whether the pawl i8 is coupled to the toothed wheel IE or M, respectively.

For guiding the pawl [8 to engage and to disengage the shoulders on gears I4 and I5, said pawl has a point or head at that end which is most remote from the pin lSa. This point enters a guiding slot Zia having oblique entrance edges 21b. This slot is formed in a movable guiding member 2! (Figs. 1, 2 and 7), and the point of the pawl 6 is in the guiding slot 2la, when the shaft 16 is at rest (that is, when the actuatoris in' its full cycle position). When the shaft l6 rotates, the point of the pawl l 8 engages one side or the other of a stationary guiding rail '22 whichis curved along a circular arc (Fig. 1). Thus, thepawl I8 is positively guided during that part of the'rotation of the shaft i6 during which the point of the pawl is outside of the slot Zia. The guiding rail 22 is preferab'y resiliently suspended. In other words, the slotzla anathema 22 together guide the pa wl iil durin g th'e whole revolution of 360. Normally, the'guidin'g member 2| with ing slot 2! a is in its'mid'dle or central position (Fig. '7) and then the pawl I8 is disengaged from the shculde'rs on gearsli and I5. When in the manner describedb el'ow the guiding member 2| is moved to either side, it rocks the pawl 18 correspondingly to engage the corresponding'shoulder on the gears or' l5.

A rocking arm'23 ispi'votally journalled on the stationary pin 24 and one end 23a (Figs. 1 and 1 of this a'ri'n enters the space between two cam discs '25, 26, which are secured to the shaft l3 and consequently rotate when the motor runs. This's'wings the arm 23 to and fro in a, reciproeating or pendulous motion on the pin 24. The opposite end of this arm has a recess 21 (Fig. 2).

"Iw'oeoupling rods 28, '29 are displaceably journalled ca ins 30 (Figs. 1 and 2) secured to the stationary plate (frame part) 3| and entering oblong slots in'the rods. Said rods may, therefore, be displaced in their longitudinal direction, and springs 32 are tensioned between said rods and stationary pins 33 and tend to lift the rods to their uppermost position. At their upper ends, these rods carry pins 34'entering slots 35 of an angular piece 36 which is displaceable laterally, that is parallel with the shaft IS, on a stationary shaft 31 (Figs. 1 and '7)s'ecured between the two intermediate 'walls 38 and 39 of the machine frame. The angular piece 36 is rigidly connected with the guiding member 2| to form a rigid unit, normally kept in its centrarposmon between the Walls 38 and '39by a spring 40, as shown in Fig. '7. When the angular piece'36 and the guiding member 2| are in this central position, the pawl I8 is disengaged from the shoulders on gears l4 and I5, as mentioned above. The angular piece 36has aprojection 4| (Figs.'1, 2 and 4), which rests against theinside of the downwardly projecting part (tongue or ofl'set) 42 of the locking arm 43. At one end said locking arm is rotatably J'ournalled on the pin 44 which is secured to an offset part of the side wall 38. .The opposite (outer) end of the locking arm 43 is embraced by the fork-shaped upper end of an arm 45 which is rotatably-journa-hed on the pin 46 on the side wall 39 and is pressed by a spring 4'! in such direction (clockwise in Figs. 1 and 11) that thepart 42 engages the projection 4!.

A pin 48 (Figs. 1, 2 and 6) is riveted to the angular piece 36 and enters the space between its guid- 28 and the key two double-conical pins 49 and 50. Th pins 49 and 50 may also be described as having the shape of hyperboloids of rotation. These pins are riveted to the back ends of stop pawls 5|, 52, respectively, rotatably journalled on a pin 53 secured to the side wall 39. Around this pin a torsion spring 50I is wound, acting upon the two stop pawls so that the double-conical pins 49, 56 are pressed towards each other to engage the pin 48.

When the machine is at rest and nooperation of calculation is being carried out, the two stop pawls 5|, 52'engage their respective stop shoulders 54, 55 of two bufier discs 56, 5'! (Figs. 1, 3, 10 and 11), said torsion spring 50! pressing the points of the pawls inward against the periphery of-said buffer discs which are rotatably journalled on the main shaft 58 of the machine, which carries the actuator. Between the two discs 56, 57 a strong bufier ccmpression spring 59 is arranged which presses those discs to engage an eccentric bushing or sleeve 6'0 (Figs. 1, 3, 8 and 9). This bushing is either itself non-circular, for instance, oval or elliptic in cross-section, or is eccentrically journalled on a screw or stud bolt 6! which is secured, as by riveting to a cam disc 62 rigidly connected with the main shaft 58. A nut 63 threaded on the screw 6| serves to keep the bushing 60 in its angular positicn as set on the screw 6|. It is to be observed that the cam disc 62 is eccentrically arranged on the main shaft 58 and the circular slot 64 cut in said disc is conse- 'quently eccentric in relation to the main shaft 58. A roller 65 (Figs. 1 and 5) enters said slot and is journalled on a three-armed lever or release arm 3H1 which is rockably journalled on the stationary pin 61. The horizontal arm 66 of said lever extends inwards through the space between the rods 23 and 29 (Figs. 1 and 2) to engage the edges 63 of said rods from above. At this place the arm 66 is broadened so that it can cooperate with the edges 68 of both reds 28, 29, as is shown in Fig. 2. To the lower arm of the release lever 3l0 a three-arm or three-branched hook 69 is rotatably journalled on the pin 16. A torsion spring H is wound around said pin and tends to rock the hook 69 counterclockwise in Figs. 1 and 5.

Under the action of this spring'the back arm 69a of'the book 69 engages a pin 12 secured to the intermediate wall 39. In addition, the book 69 has an angularly disposed portion 13 which extends laterally below the projections 1'4 (Fig. l) on the two keys 75 and 76, that is the multiplication or revolutions key I5 and the division or subtraction key 16, respectively. These keys are'ro-tatably journalled on a stationary shaft 7'! and are acted upon by individual springs 18 pressing the back end of the key against the stationary guide 3|. In addition, these keys have hooks 79 engaging the edges 68 of the rods 28, 29 from above to normally prevent the spring 32 from lifting seid rods, that is when the key 75 or 16, respectively, is not depressed. It is to be observed that the key 15 cooperates with the rod 'lfiwiththercd29. Each key75 or F6 has a hook 8!, which is rockablv .iournall-ed on a pin 86 on the key and is-pressed by a spring 82 to engage the pin 83 on the key. The points 84 of said hooks are somewhat lower than the striking edges 68 of the rods 28, 29, when said rods are in their position cf rest. The keys 15, 1B are integrally formed with the arms 85 and also w th the arms 290 and 29L respectively. The arms 85 of said keys engage the pin saw of an -of the keys 15 and 16, respectively,

angular piece or contact lever 33! which is rockably journalled on the stationary in 333 and controls the electric motor contacts 334. When one of the keys 15, 1B is depressed, the contact lever 33! is rocked to close 334 starting the motor. The arms 290 and 29! enter in wellknown manner a recess in a plus-minus-control plate 281 which is arranged below the base plate of the machine, as shown in Figs. 1 and 5. Reference is made to the corresponding parts 299, 23!, 281 of U. S. Patent No. 2,398,286, issued April 9, 1946.

A lever 86 (Figs. 1, 4 and 5) is rockably journalled on the stationary pin 81 secured to the frame 88. This lever has four projections 89, 9D, 9!, B2. The projection-89 (Figs. 1 and 5) extends through a hole in the intermediate wall 39 above the arm 69a of the hook 69. The projection 99 forms a striking edge for the lever 21! which is rookably journalled on the stationary pin 325 and with its surface 93 engages the projection 99. The projection 9| engages the arm I02 which, in a manner shown in U. S. Patent No. 2,398,286 is acted upon by the tens transfer hook or lever for the totalizer wheel of the highest denomination in the results register. When a ten is carried into that totalizer wheel the arm I02 is swung in the direction of the arrow A in Fig. 5, that is clockwise, as is described in detail for the part I92 in U. S. Patent No. 2,398,286. Finally, the projection 92 engages the lever 45 (Figs. 1, 5 and 11) to rock that arm, when the lever 86 is swung counterclockwise. A tension spring 94 presses the arm 86 and its projection 9! into engagement with the arm !92.

The driving lever 261 (Figs. 1 and 5) drives the swing lever 241, and also the plus-minus control plate 281 in the manner shown in detail in U. S. Patent No. 2,398 286. The lever 241 effects the shifting and the control plate 281 pulls down the keys 15 and 16 during the calculating operations. This control plate 281 is set to its position and position by means of the reversal lever 294, depending on the setting of the angular piece 36 to which the reversal lever is directly connected.

Depending upon how said angular piece and consequently the control plate 281 are set said control plate engages one of the projections 29D, 29! of the multiplication key 15 or the division key 18, as described for the corresponding parts 281, 298, 29! in U. S. Patent No. 2,398,286.

The key holding-down-lever 95 (Fig. 1) which is rotatably journalled on the stationary pin 96 of the wall 39 has a front angular portion 91 extending through a hole in the intermediate wall 39 to engage the angular lower ends 98 (Figs. 1 and 2) of the lifting rods 28, 29 from above. Said lever 95 has a curved cam slot 99 (Fig. 1) engaged by the pin 213 secured to a small standard or tongue on the swing lever 241. In addition, a pin 95a (Fig. 11) is riveted to the key holdingdown-lever 95 and enters a slot of the contact lever 33! to swing that lever for closing the contacts 334 when the lever 95 is pressed downwards.

An impulse arm or lever I80 (Figs. 1 and 11) is displaceably journalled at its upper end on the pin 53 for the stopping pawls 5!, 52, said impulse lever having an oblong slot through which said pin passes. The upper end of this impulse arm is fork-shaped and has two angular prongs I! resting on the upper sides of the two pawls 52. At its lower end this impulse lever carries a pin I03 resting in a slot !84 of the contact lever 33!. 1 The slide 24! (Figs. 1 and 5) is controlled by the motor contacts the control lever of the machine as described with reference to parts 24! and 26! in U. S. Patent No. 2,898,286, this lever serving for setting the machine to multiplication and to division with automatic shifting. Depending upon the setting of this lever the slide 24! is in or out of the path of motion of the pawl 69. When the machine is set to multiplication the slide 24! is out of the path of motion of the pawl 89, but when the machine is set for division, the slide 24! enters the path of motion of said pawl.

The release arm 3!!) (Figs. 1, 11 and 12) acts directly on the hook 358 which is integral with the subtraction setting lever 3580a. This lever 358a extends outwards through a slot in the casing !05 of the machine. In the embodiment shown the machine has, in addition to the multiplication or positive multi-revolutions key 15 and the division or negative multi-revolutions key 18 also an addition key, as in U. S. Patent No. 2,398,286, but no subtraction key, Thus, the machine is set to subtraction by pressing the lever 358a downwards manually to its lowermost position, and when the division key 16 is depressed, the machine performs an operation of subtraction as described in connection with Fig. 16 of the patent just mentioned. For this purpose the release arm 3!!) has an angular projection 310a pressing against the edge 318 of lock 358 when the latter is depressed due to the fact that the operator presses the lever 358a downwards to its lowermost position (for subtraction) or due to the fact that the addition key has been depressed manually. Figs. 1 and 11 show the lever 358a in its uppermost position, while Fig. 12 shows the same in its lowermost position. When the slide 380 is pushed inwards, that is to the right in Figs. 1 and 11, for instance, due to the manipulation of the clearing key 486, the cam 380a of this slide acts on a pin 198 extending through a hole of the intermediate wall 39 and secured to the lever 45. This rocks the lever 45 and moves the lockin arm 43 to the left in Fig. 1 and counter-clockwise in Fig. 4 so that the part or offset 42 of that looking arm releases the tongue 4! of the angular piece 38. Under the action of its spring 40, the angular piece 36 with its guiding slot Zia is restored to its neutral, central position so that .the coupling pawl I8 is disengaged from the shoulders on gears !4 and !5. If the main shaft 58 rotates, when the clearing is started, such rotation is thus stopped, as soon as the current revolution has been completed. The main shaft 58 cannot be re-started again during the clearing operation due to the fact that the lever 45 keeps the locking arm 43 rocked aside so that its offset '42 does not lock the projection 4!. Consequently the guiding slo-t 21a and the coupling pawl !8 are restored to their inoperative neutral position, before any of the shoulders on the gears l4 and I5 come around to the pawl !8 during rotation of the gears l4 and !5. When the slide 380 is displaced to the right in Fig. 11, the pin 4l2 thereon rocks the arm 4!! clockwise in Fig. 11, said arm being rockably journalled on the pin 333. Consequently, this arm acts on the pin 331a and the contacts 334 are closed for the clearing operation. In clearing operations effected due to the manipulation of the clearing key 406 or when the machine has been set to addition or subtraction and consequently the arm 4! has been swung clockwise in Figs. 1 and 11, the downwardly extending projection 4! !a of that arm engages the upper side of the angular projection 269 (Fig. 5) of the lever 21!. This prevents all shifting of the actu- -2,398,286,-the toothed wheels 385,'388, 394 are driven-by the motor under'thecontrol of the r 7 atorduring operatic of addition. subtraction and clearing.

As is described in detail in U. S. Patent No. (Fig. 1)

:tion (zeroizing).

A disc I01 (Figs. 3and 11) is rotatably journailed on the main shaft '58 and carries twopins I08, I09 which enter into the holes III] or III respectively of the stop'discs 56 or 51, respectively, and are guided in saidholes. In clearing clearing operation from being started as long as the'main shaft 58:rotates. Similarly, the pro- 'jection'400c engages the periphery of disc I01 when the clearing key 405 is the actuator rotates. Not until aftersaid shaft has been stopped in its full cycle position by the stop pawls 5|, 52,'d0es the spring '408-pullthe projection 4000 into 101 and this-swings the coupling arm392 counterclockwise so that the clearing is effected. Thus, said disc-I01 is stopped and locked, but nevertheless the main shaft'58 may move slightly beyond its position of rest while compressing the buffer spring 59. For instance, in anoperation of'addition the disc 51 may move somewhat counter-clockwise, because-the pin I09 can move somewhat in the hole I I I. Thus, thG'diSCS-FS I Mode of operation For the various kinds of operatiomthe device described acts as follows:

Multiplication The "control lever of -the rnachine (seelever 24I -controlled thereby to be'moved out of the path of inotiori of the hoo'k '69 (Figs. 1 and 5). At this setting, the plus-minus-control plate 281 is locked, as described in detail in said patent, and it is consequently not'moved by'the eccentric-driven lever-261 in'its rocking motion.

After the multiplicand has been entered in the actuator in"wellknown manner; the multiplication-key '15 (Fig. 1) is depressedcausingthe the'recess 'I01a of the disc lifted rod 28 is moved rocks the coupling pawl pled to the shoulder slot arm fof'xthat key to rrockthe contact lever 8M clockwise-in Fig.:1in:such manner ithatthe electric contacts 3'34for the motorare closed. When the *motor starts, :the swinging 'arm 43 (Figs. 1 and 4) :is rocked bythe cam discs *25; 26.

t e operator depresses the'key 15,'its oblique edge coupling rod -28so that said rodis free and displacedupwa'rdsby lts spring 32. Then, the upper part of this roden-terstherecess 21 (Figs. 1 and 2) 'of the rocking arm 23 and consequently the by the rocking arm 23 so that said rod is displaced laterally-to the left in Fig. 2. During this operation,-the pin 34 on the :rodacts upon the angular piece 36 causing also that piece to be displaced-to the left in Fig. 2 and consequently the guiding slot 2Ia (Fig. 7) I8 in the same direction. Consequently, the coupling pawl becomes couon the gear couples the mainshaft 58 with the motor to be springdl) (Fig. 7) cannot restore said angular piece toits neutral central position. When the angular piece 36 is displaced in the manner-just described,-the pin 48 secured thereto follows and is moved to the left in Fig. 6 to act upon the conical pins 49,50 so that they are pressed apart pawls 5| 52 are lifted from are lifted, they themselves lift the impulse arm I00.

When the'cam slot disc-62 (Figs. 1 and 8) secured to-the shaft 58 begins moving, its eccentric slotidzroeks the release arm 3I0 clockwise in Figs. 1 and 11, said release arm engaging the 134 by means of a roller 65. The horizontal arm GG-ofthe release arm 3I0 then-is lowered towards the strikingedge 68 (Figs. 1 and 2) on the coupling rod 28 an'dthus sition ofrest "shown-in Fig. 1.

-Because of the depression ofthe key 15, the

beginstomOVe counter-clockwise under the action (if-the eccentric camslot 64.

When "the multiplication-key 15 is kept depressed, its striking surface 14 (Fig. 1) is in the path-of motion of the angular portion 13 of the hook- 69, when said hook is rocked by the release arm 3 I0 at the rockingmotion ofsaid armas just pin-12' andslides'along said pin during its motion and with its point strikes the tongue 89 of the lever 86 (as shown in the position 1 of the hook 69 in Fig. 5, in which the position dis the position of rest of that hook). This swings said arm 86 counter-clockwise in Fig. 5 so that its tongue 92 strikes the arm 45 and rocks it counter-clockwise in Fig. 1, that is to the left in Fig. 4. The locking arm 43 follows in that motion and its part 42 is moved out of the path of motion of the part 4| of the angular piece 36 which now is restored to its inoperative central position by the spring 40 (Fig. '7). This restores the pin 48 secured to that angular piece, to its central position shown in Fig. 6 and the stopping pawls are released. Their torsion spring 59| now presses them downwards against the periphery of the buffer dis s 55, 51. During its continued rotation the coupl ng pawl I8 is acted upon by the oblique surface 2 b of the guide member 2| (Fig. 7) now in its central position and, consequently. this pawl is drawn out of its engagement with the shoulder of the gear |5 so that the main shaft 58 is disconnected from the motor. When the stopping projec ions 54, 55 of the buffer discs 56 or 51, respectively, are just in front of the points of the stopping pawls 5|. 52, the torsion spring 50| presses these stopping pawls into engagement with said stop projections 54, 55. Because the main shaft 58 now is rotating in revolutions, that is counter-clockwise in Fig. 1, the stop projection 54 strikes the stop pawl 5|. The kinetic energy of the rotating actuator on the main shaft 58 is absorbed by the buffer spring 59 so that the rotating parts are gently and reliably stopped. It is to be observed that during the whole bouncing action, the stopp ng pawls 52, 5| engage the stopping projections 55, 54 permanently and without any relative motion. This means that there is no risk that the stopping pawls will swing out and be disconnected, but on the contrary, the rotation is rapidly and reliably stopped. It is to be observed that for example in a revolutionthe stop pawl5| may be depressed to its lowermost stopping position almost one half revolution before the main shaft 58 is stopped. As is shown in Fig. 10, the disc 55 has substantially the shape of a half-circle and permits the stopping pawl 5! to swing down to its stopping position approx mately one half revolution of the main shaft 58 in advance. Thus the stopping projection 54 strikes the stopping pawl 5|, the disc 51 continues rotating somewhat counter-clockwise, so that the stop pawl 52 can easily be rocked down against the stop projection 55,

When in the manner just described the lever 86 is rocked counter-clockwise in Figs. 1 and 5 under the action of the hook 69. the lever 2'|| is released from the tongue 99 and is lifted upwards by its spring. This releases in the manner described in U. S. Patent No, 2,398.286 a shifting impulse, because the pawl 255 (Fig. 5) is thus released and enters the path of motion of the driving lever 251, which then drives the swinging lever 241 carrying the pawl 265 with which the stepshifting mechanism of the actuator may be coupled. When thus the swinging lever 24'! beg ns moving to the left in Fig. 5 the pin 213 secured to said lever acts upon the arm 2' and presses it downwards in Fig. 5 so that the tongue 90 of the lever 86 again engages the surface 93 and locks the arm 2'" in its lowermost position shown in Fig. 5. During this operation, said pin 213 moves in the slot 99 (Fig. l) of the key depresser or key holding-down member 95, which is consequently also pressed downwards so that its angular portion 91 presses the bent lower ends 98 of the coupling rods 28, 29 downwards. Consequently, said rods cannot be released and cannot be liftedupwards to engage the rocking lever 23. Thus, the main shaft 58 and consequently also the actuator thereon cannot be started, as long as a shifting operation is being carried out.

When the multiplication key 15 returns to its position of rest, the contact lever 33| is still kept in its operative position and keeps the contacts 334 closed, because the pin |93 of the impulse lever I (Figs. 1 and 11) presses on the contact lever, said impulse lever being now raised to its uppermost position by the lifted stop pawls 5|, 52. Not until after the stop pawls 5|. 52 fall down to engage the stop projections 54, 55 does the impulse arm I99 move downwards, that is. not until after the main shaft 58 and the actuator thereon have reached their position of rest or full cycle. The electric contacts 334 are consequently kept closed. This is very important for a rapid and reliable action of the machine.

Division For division the control lever of the machine, which corresponds to lever 2ll| in U. S. Patent No. 2,398,286 is set manually to its position for division. Thus, the slide 24! is moved into the path of motion of the hook 59 (Figs. 1 and 5). As is described in detail in U. S. Patent No. 2,398,286, the plus-minus-control plate 281 is now free and can be displaced, when a shifting impulse is applied thereto.

The dividend is now entered in well-known manner in the actuator and is transferred to the results register. The actuator and, if necessary, also the revolutions counter is cleared and then the divisor is entered in the actuator, which is now in the usual manner tabulated to its extreme left position, that is to the highest decimal denominations of the results register. To start the machine the operator now depresses the division key 16 which then causes the contact lever 33| to close the electric contacts 334. In a manner analogous with that described above under the heading Multiplication, the rod 29 is lifted and the main shaft 58 is started to rotate clockwise in Fig. 1, that is in a revolution.

When now the cam slot disc 62 rocks the release arm 3|0, the hook 69 (Fig. 5) follows and with its edge engages and slides on the slide 2 as shown in position e in Fig. 5. The slide 24| thus prevents the hook 69 from moving to its position after the division key 16 has been restored to its position of rest. In other words, the hook 69 will not act upon the part 89 of the lever 86. Said lever remains thus unactuated'and the main shaft 58 with the actuator thereon continues rotating in revolutions until the capacity of the results register is exceeded and, consequently, a ten is carried to the highest denomination of that register. This swings the arm I02 in the direction of the arrow A in Fig. 5 and this motion is transferred to the lever 86 which is consequently swung counter-clockwise. As described above under the heading Multiplication this causes the striking surface 92 to swing the arm 45 (Figs. 1 and 4) and consequently also the looking arm 43. Consequently, the angular piece 35 is now free and it is restored to its inoperative, central position so that the main shaft 58 is disengaged from the motor and the actuator is resiliently stopped by the stopping pawls 5|, 52.

'When the lever 86 in the manner just described is' rocked counter-clockwise in Figs. 1 and 5 under the action of an impulse from the arm 102 at the tens transfer, the arm 21 pi-'ojection 96"andthis releasesin the manner de scribed-in US, Patent NQ.- 2 ,398,286 shiftihg irn pulse, because the pawl"265- out into the path of motion or the driving level" 261. Consequently said lever now drives the swinging lever 24? carrying thepawl 265'toshift the actuator one step. when the angle piece 36 is moved to its outermostposition position) it-acts in well-known manner on the-plus-minuscoupling arm 294, arid saidarrii then sets the controlplate 28's to'pulldown the multiplication key by means of its projection 290. The'driving lever 26? by means of the plus-minus-driving"lever 2l4"n0w acts'on the control plate 28! to displace it and to cause it to pull down the multiplioation key 15'. V

Thus, the automatic division is well known manner.

Addition" When the item (addend) has been set in theactuator in well-known manner, the actuator upon the depression of the addition key performs'one single revolution in the manner described above'under the headingMultiplication and is stopped. Then the actuator is automatically cleared in the manner described-in U. S. Patent No. 2;3 9 8,286 due to the factthat the slide 380 is displaced to the right in Fig; llywhenthe hook 358 is moveddownwards (counterclockwise) at the depression of the additionkey.

Subtraction Subtraction is carried out similarlfi asan operation of addition. The minuend isset' in the actuator, the setting lever 358a forsubtract'ion is moved downwards by the operatorand the division key lli'is'dep'ressed. The actuator therefore performs a revolution, is stopped and automatic'ally cleared; v

Certain modifications maybe made in the device shown and described within the scope of this" invention. Thus, assistance-between the strik ing edges or stopping shoulders 54, may be Continued in adjusted by' substituting exchangeable cylindricrollers' onthe stud bolt 6|, forthe eccentric fifl. The striking surfaces or edges with which the discs 56, srengage the eccentric ma be made oblique, instead-of parallel. Thisrendefs it possible to adjust the distance between the shoulders 54; 55 still more, because'in suchcase the eccentric, in its different angular" positiohs-s'etssaid distance to difiere'nt Values? What we claim is:

1; In' a power'actuate d" calculating machine; a ro'tatably mounted actuator; means for'rotating said; actuator in opposite directions; a pair of members rotatably mounted coaxiallywith saidactuator and formed with shoulders; resilient for opposing rotation of said actuator;

2. In a power actuated calculating machine:-

a rotatably mounted actuator, means for rotat-' lng said actuator in opposite; directions, a-pair-of;

is released from theis released-and springs "rotatably' mounted actuator, means members rotatably mounted co'aiiially with said with shoulders facing each*- actuator and formed other,- re'silient means-roe opposing rotation or rotatabl'y mounted actuator, means for rotating said actuator in opposite directions;- zit-projection rotatablewith'said actuator,- a pair of members rotatably mounted coaxially' with' said actuator andhavins'suhstantially radial surfa'ces engaging opposite sides of said projection; a buffer spring between said membersfor urginig'said faces'into contact with said projection; said' members hav ing shoulders; anda pair of arresting p'awls co operablewith'sai'dshoulders for stoppinerotation' ofsaid actuator.

5'. Ina power actuated calculating machine; a" rotatablymounted actuator, means for rotatingsaid sandstone opposite directions, a projection rotatable withsa'idactuator, a pair of members rotatably mountedwoaxially with said actuator an d having substantially radial surfaces i engaging opposite sides" ofs'aid projection, a; boner spring between said rrlerribe'r for-urging said faces into contact with said projection, said members having shoulders} said projection comprising aneccentric element; means for adjusting the e'c'cen tricitycf said element to thereby vary" thespace between the shoulders" on said members; andl'a pair or arresting p'aw'ls cooperable with said shoulders for stopping rotation 01' said actuat'on' 6." In'apower actuated calculat'ii'ig 'rha'chine; a= rotatably mounted actuator,- saidactuator in opposite directions, at projection rotatable with-said' -actuator, a pair-"of members rotatably'm-ounted coaxially with said" actuator andhaving-substantially radial surfaoes engagingopposite sides of-said projection, a buffer spring between said'members 'for urging Sam facesinto contact with said projection, said members hav-' ing shoulders'sai'd projection comprising a, cylin-T dr'ical element,- said element; element of difierent diameter in order'tovary V the space between the shoulders on said members, and-apai'r of arresting pawlscooperablewith sald' shoulders for stopping rotationof said actuator.

7.- In a "power actuated calculatingmachine; a rotatably mounted actuator, meansfor rotating said actuator rotatable withsaid actuator, apair of members rotatably mounted 'coaxially with said" actuator and having:arcuateperipheries of notmor'e than IBO-K-each membe'r havin'g a shoulder formed ad jace'nt-to one'endof'its periphery; a buffer spring" between said" members for' urging the members into' contact with-"said projection, and apair of arresting pa-wlscooperablewith saidshoulders" forstopping rotation' of said actuator.

8; In a power actuated calculatin g machine, a''-- rotatably' mounted actuator; meansforrotating said actuator in= opposite directions, a pair of members rotatably mounted co'axiallyT with said actuator and formed; with shoulders; resilientmeans for limiting rotation of said member 11318,? tive to said actuators-a, pair of'arresting pawls co'-T operable with said shoulders for strn'niung rotation of: said disengaging both said" pawlsfrom said shoulders 9. In a poweractuated calculating machine, a

said members relative to"said-' actuator',' means for adjusting the space between said shoulders means for rotating" meansfor removabl'y mounting" hereby it may be" replaced by an in opposite directions, a projection actuator, and' meansfor simultaneously" forrotetin'g for rotating said shaft and actuator in opposite directions, a pair of members rotatably mounted coaxially with said actuator and formed with shoulders facing each other, resilient means for limiting rotation of said members relative to said actuator, a pair of arresting pawls cooperating with said shoulders for stopping rotation of said actuator, a disc rotatably mounted on said shaft, a clearing key operable only when said disc is in its full-cycle position, each of said members being formed with an aperture, and a pair of pins of smaller diameter than said apertures extending from said disc into said apertures, for limiting relative rotation between said members and said disc.

11. In a power actuated calculating machine, a shaft, an actuator carried by said shaft, means for rotating said shaft and actuator in opposite di rections, a pair of members rotatably mounted coaxially with said actuator and formed with shoulders facing each other, resilient means for limiting rotation of said members relative to said actuator, a pair of arresting pawls cooperating with said shoulders for stopping rotation of said actuator, a disc rotatably mounted on said shaft, each of said members being formed with an aperture, a pair of pins extending from said disc into said apertures, said disc being formed with a notch in its peripheral surface, and a clearing key cooperating with said peripheral surface and engageable with said notch when said disc is in its full cycle position determined by engagement of said pawls with said shoulders.

12. In a power actuated calculating machine, a

rotatably mounted actuator, an electric motor for rotating said actuator in opposite directions, an electric switch in the circuit of said motor, a pair of members rotatably mounted co-axially with said actuator and formed with shoulders, resilient means for opposing rotation of said members relative to said actuator, a pair of arrestingpawls cooperable with said shoulders for stopping rotation of said actuator, and means operative by said pawls for maintaining said switch closed when the pawls are disengaged from said shoulders.

13. In a power actuated calculating machine, a rotatably mounted actuator, an electric mot-or for rotating said actuator in opposite directions, an electric switch in the circuit of said motor, a pair of members rotatably mounted coaxially with said actuator and formed with shoulders, resilient means for opposing rotation of said members relative to said actuator, a stationary shaft, 9. pair of arresting pawls pivotally mounted on said shaft and cooperable with said shoulders for stopping rotation of said actuator, an arm movably supported on said shaft, projections on said arm and engaging said pawls so that disengagement of said pawls from said shoulders moves said arm, and means responsive to the movement of said arm for maintaining said switch closed.

ERIK GRIP. STURE TOORELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,566,979 Schuman Dec. 22, 1925 1,730,014 Reece Oct. 1, 1929 2,068,899 Anneren et a1 Jan. 26, 1937 2,279,474 Machado Apr. 14, 1942 1,050,388 Pike Jan. 14, 1913 FOREIGN PATENTS Number Country Date 551,311 Great Britain Feb, 17, 1943 

